Mittens and gloves are two well-known types of hand coverings. A mitten is designed to enclose almost the entire hand within a large, bag-shaped primary structure. Most mittens also include an ancillary portion to receive the wearer's thumb. As is well known, a glove is different from a mitten because it is shaped to exactly fit the wearer's hand and includes separate digit portions that are sized and shaped to receive each of the wearer's fingers. Beyond the obvious physical differences, mittens and gloves each have their own distinct advantages and disadvantages.
The design of a mitten provides excellent heating ability due to the use of a primary body portion to form a large heat-retaining inner pocket or cavity. Furthermore, by loosely enclosing most of the hand within the single heat pocket, the heat generated by the hand is dispersed throughout the pocket and therefore contacts most of the wearer's hand. In this manner, the large quantity of heat given off by the palm and back portions of the hand is also used to warm the fingers. This enables a mitten to be capable of keeping a wearer's hand warm even when the ambient temperature is extremely low.
The primary disadvantage of a mitten lies in its almost total elimination of the hand's manual dexterity. The wearer can at best grab an object between the thumb and finger portions of the mitten in a manner similar to a bifurcated claw. The use of a single primary pocket does not allow any of the hand's long digits to be independently wrapped about an object. Therefore, a mitten can only be used when manual dexterity is not required.
The advantage of a glove is that it allows the wearer a manual dexterity that is similar to that of a bare hand. The fingers can be moved independently, thereby allowing even complex manual manipulations to be accomplished.
It is well known that gloves cannot provide adequate heating of a wearer's hands when extremely cold temperatures are encountered. A glove's heating ability is directly related to the size of the primary heat pocket and the thickness of the insulating layer sandwiched between the glove's inner liner and outer shell. To compensate for a glove's smaller heat pocket, many manufacturer's increase the thickness of the insulating layer. Unfortunately, any increase in insulation thickness reduces the dexterity allowable when the glove is worn. To maintain some degree of manual dexterity in low temperature applications, it follows that the heating ability of a glove must be partially sacrificed
The heating ability of a glove is further diminished by a lack of internal air circulation. In an insulated glove, the interior liner is in tight contact with the hand and especially with the fingers. When the wearer inserts his or her hand into the glove, the liner is pushed outwardly and this causes a compression of the insulation between the liner and the less flexible outer shell. As a result, the liner and insulation form a tight seal around the fingers. This effect substantially isolates the fingers from the primary heat packet formed by the glove around the palm and back portions of the hand. Due to the lack of air flow to the fingers, the only method of maintaining the temperature of the fingers is by the circulation of blood within the fingers. During cold weather, a glove wearer's fingers can easily become cold thereby producing the general feeling of having cold hands. This is an uncomfortable situation that the wearer will most often attempt to overcome by placing his or her gloved hands within the outer pockets of a coat.
There are situations when the above noted glove disadvantages are extremely noticable. Many cold weather sports are practiced in frigid weather and at the same time require a significant measure of manual dexterity from the user. Skiing is one such example. This sport is practiced on mountain slopes in which below zero temperatures and strong winds are frequently encountered. A skier is required to constantly hold and maneuver the ski poles while proceeding down the hill. In addition, should the skier fall, the skier may he required to manipulate portions of the ski bindings in order to replace the skis on the boots. Even such mundane tasks as the zipping or buttoning of a coat can require a degree of physical dexterity that is unavailable when mittens are worn. Therefore, a skier will often have to endure a glove's inadequate heating of the fingers so that a sufficient level of manual dexterity is available.